Why is my check engine light on but no codes?

One main reason that a check engine light comes on with no code being stored is that there is a software error.

This is often the result of something being wrong with the OBD reader that the driver, parts store, or mechanic shop is using.

Most frequently, the software errors stem from a low-level OBD reader being used.

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Why is my check engine light on?

Your Check Engine Light may be indicating a simple problem that's easy to fix—such as a loose gas cap that needs to be replaced.A flashing Check Engine Light indicates that your vehicle's engine is in serious trouble, whereas a steadily lit one means less urgent service is needed.

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Why is my traction control and check engine light on?

The Traction Control Light indicates your car's traction control system is active.Traction control is necessary to maintain grip in slick conditions.Common signs include the Check Engine Light coming on, car braking inconsistently, and the traction control switch not depressing.

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Why is my check engine light on Volkswagen?

VW Check Engine Light Flashing When your Volkswagen check engine light is flashing, means the onboard diagnostic system has detected a misfire.This is due to fuel not getting burned in the cylinder.This problem is typically caused by a bad spark plug or ignition coil.

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Why is my Mini Cooper check engine light on?

When you see the check engine light illuminated in your dash, it means your Mini Cooper has detected a problem within its OBD system.If the Mini engine light is flashing yellow or red, it is in your best interest to take it to an Independent Service Center for diagnosis right away.

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Why is my car shaking and check engine light on?

Check engine light flashing car shaking is a clear sign of trouble.Vibration or shaking may be caused by misfires, poor fuel pressure, or faulty spark plugs.You should also know that a defective idle air control valve might make the engine idle drop significantly.

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Why is my check engine light on and car shaking?

Check engine light flashing car shaking is a clear sign of trouble.Vibration or shaking may be caused by misfires, poor fuel pressure, or faulty spark plugs.You should also know that a defective idle air control valve might make the engine idle drop significantly.

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Why is my check engine and battery light on?

The battery light will come on if the charging system and battery voltage drops below a minimum set by the factory.The check engine light is letting you know that there is a problem that a code has been set in memory that can be diagnosed.Check the charging system and repair or replace the altern...

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Check engin light codes?

Toyota engine code 402

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Why is my engine light on but nothing seems wrong?

Normally, the appearance of a check engine light indicates a problem somewhere in your vehicle, but nothing seems amiss.If you think this is the cause of your check engine light, simply twist the gas cap until you hear a clicking sound.It doesn't have to take a mechanical issue in order for this ...

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Why is the check engine light on when the scan does not return a code?

It is possible to mistake a Maintanence required light for a Check Engine like. One is a problem indicator, the other is merely a service reminder dummy light. Check your owner's manual to be sure it is not the dummy light.

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Can you read codes without check engine light on?

Hi there.In short, yes; it's possible to diagnose a problem with a vehicle even if the check engine light does not illuminate.A professional mechanic would start by downloading any error codes store in your 2005 Ford Explorer's computer.

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Why is my check engine light on after my battery died?

A dying car battery means low voltage.That means your car's computer, which is responsible for reporting error codes, is also receiving low voltage.As a result, an error code will be generated which will in turn trigger the Check Engine Light or even the Battery Charge Warning Light.

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Why is my check engine light flashing and car shaking?

Vibration or shaking may be caused by misfires, poor fuel pressure, or faulty spark plugs.A misfire always develops a disproportion in the motor, causing vibration or shaking.Another issue that may cause check engine light blinking car shaking is a broken engine mount.

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Why is my check engine soon light on in my 1997 town country ran a diaganostic came up with codes 3221 What do they mean?

Are you sure that is right? I cant find anywhere where the codes even go that high.

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Why does the check engine light come on but the car still runs?

This condition is a "limp in" mode programed into your cars computer so that it still can be driven even thou a problem has been detected. In this mode the engine runs on preset program that does not require feedback from sensors on the engine to run. This "OPEN LOOP" mode does not update the com...

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What could cause no power with no check engine light?

If you mean no electrical power then the computer couldn't give you a warning light because it has no power to operate. Common causes of lack of electrical power include a blown fusible link, a blown main relay ( not all cars have them ), a dead battery or a severe short.

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Why is the airbag and check engine light on?

There are a number of reasons why your airbag light has come on or is flashing. We will cover a few explanations that may help you identify where the problem may have originated from. First and foremost if the airbag light is on or flashing, the SRS system is inactive. Therefore, if you get into ...

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2001 Pontiac Sunfire why is the check engine light on?

The Check Engine light is on because the computer has detected a problem with the emissions system. It may be nothing more than a loose gas cap or something more serious. You will need to get the computer scanned with an OBD2 scan tool. Some Auto Parts store will do this for free in some states. ...

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Why is check engine light on 2005 Hyundai elantra?

take it to autozone and they'll tell you fro free

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Why is your check engine light on your 2004 Avalon?

It is on because u did not put the cap back on tight enough.

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Why does my check engine light blink when I accelerate?

A blinking light usually indicates a severe engine misfire allowing unburned fuel to be dumped into the exhaust system.There it can quickly raise the temperature of the catalytic converter to a point where damage is likely, requiring an expensive repair.

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Why does my check engine light comes on and off on 1991 Honda Accord?

You check engine light is signaling to you that there is something wrong with you car. You should have your car looked at by a professional.

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Why is your check engine light on all the time?

There are pages and pages of things that can cause a check engine light. You need to have it checked with a scantool. Then the code can be diagnosed and repaired.

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Ford ranger check engine light is on code's 0401 and 1400?

There was probably a letter "P" in front of those numbers. Those codes indicate a problem in the EGR (Exhaust Gas Recirculation) system. The most common cause is a part called the DPFE sensor. It can be expensive so you might want to see how much your local mechanic charges to verify the proble...

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Why is my engine malfunction light on?

The light could be a minor issue, such as a faulty gas cap, or it could mean something more serious, such as a misfiring engine.The check engine light — more formally known as the malfunction indicator lamp — is a signal from the car's engine computer that something is wrong.

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Why did my check engine light turn off?

Reason #1 – A Loose or Faulty Gas Cap – Yes, surprisingly this can cause the Check Engine or Service Engine Soon light to come on.Start by taking the gas cap off and putting it back on.You'll then need to drive the vehicle a few times to get the Onboard Diagnostic (OBD) system to reset and turn t...

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Why is my mini engine light on?

Mini coolant warning light This light will come on when coolant levels are running low and the engine is overheating.This could be due to a leak in the system or it could be a sign of a larger problem, like a head gasket failure.

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Why did my check engine light and cruise control light come on after having my oil changed?

You might need to change your O2 sensor.If the check engine light came on there will be a code set in the ecm. Have your local auto parts store read the codes for you. The codes will help you find what is wrong. Something may have gotten disconnected when the oil change was done.

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Why Check engine light on why vibrating going in overdrive?

your engine might be overheated, causing the vibrations

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My check engine light came on and speedometer stopped working?

Nope, bet it was the other way around... Your speedometer stopped working and your check engine light came on. A broken speedometer (don't know what car so I can't pinpoint it) will cause a whole bunch of codes.

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Why is the check engine on in my car?

because it needs to be checked by a mechanic to make sure it is working

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Why does my radio turn on but no sound?

Effect Of Amps Or Speaker Wires On Stereo Sound The amp can cause the car stereo not to produce any sound at all.If the fuse of the amp blows out, it could be the reason why you are not getting sound out of your car stereo.A broken wire or a bad connection can also cause sound not to come out of...

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Why doesn't the check engine light does not come on when I start my truck?

Evidently the bulb is blown out. It needs to be replaced.

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Why did my check engine light come on after an oil change?

These lights can signal something serious or something as simple as a loose gas cap.Regardless, diagnosing the problem is key.One thing that won't trigger a check engine light: a recent oil change that was done correctly.If you notice the light after an oil change, something else is wrong.

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Check light is on why?

check engine light means a problem with the emission system

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Why on a 1996 Chevy Corsica would check engine light come on but car seems to run fine?

Because the computer has detected something that needs to be resolved. Use a code scanner to find out what problem code the computer has store.

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Why does the check engine light come on your 2003 VW Passat 1.8T the codes can not identify the problem?

take it to a dealer or a qualified mechanic for a diagnostic

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Will my check engine light come on if my transmission is bad?

Transmission problems can cause the check engine light to come on as well, however it's not always as apparent as other components within the vehicle.This can result in a lack of engine power, or the transmission will not respond because there is a problem with it.

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Why do I have tail lights but no brake lights?

Check the Wiring The wiring from the fuse panel to the brake light switch and from the switch to the bulb sockets and lights could be loose or frayed.The connection and the bulb housing could be corroded.You have to change these parts if found any such problem.

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Which oxygen sensor needs to be replaced for PO Code 173 on Mitsubishi Montero XLS 2000 3.0 engine. I need to smog but my engine check light is on?

P0173 = Fuel Trim Malfunction (Bank 2)

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What is check engine code P0301 on 1999 New Beetle?

PO301 means you have a cylinder misfire in the # 1 cylinder. Can be defective spark plug or plug wire. Can also be a defective fuel injector on that cylinder.

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Why do your check engine light stay on?

have vehicle scanned to determine the problem

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Why does check engine light keep coming on?

replace your gas cap first - cheepest try. i had a crack in a vacuum hose that made it keep coming on. You have an emssions problem of some sort. It may be the gas cap and could be many other things. Unless you are knowledgable, take it to a professional if a new gas cap does not fix it. BTW, a l...

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Will AutoZone reset my check engine light?

They only read codes so we can recommend parts.Yes, we can help you clear your code; it's called telling you how to fix your damn car.Like others have said, even after clearing it, the light will come back on within 30-50 miles of driving.Happy cake day, you endlessly helpful source of information.

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Why do your check engine light keep coming on?

'Well I have a 95 Buick LeSabre, and the check engine light keeps coming on. So I asked a guy at car-x, and he said that usually occurs when you go really slow on the interstate.'

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Why does the Check Engine Soon light stay on mean?

The check engine light is on because the ECM (Engine Control Module) detects a problem with the system. Until the problem is fixed the light will remain on. Your local auto parts store can scan your ECM and retrieve the code(s) to help analyze what the problem is in order to make corrective repai...

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Why does your truck temp go up on your 2002 ram 5.9 but has no coDES?

1) low coolant level?2) bad thermostat? not opening fully3) radiator partially plugged and needs to be boiled or replaced?4) weak or bad water pump?5) radiator hoses collapsing under pressure6) bad radiator cap? not building pressure7) system air bound and coolant not circulating?

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Why is my Car overheating but no loss of fluid?

check the fins on your radiator they could be corroded and loose decreasing your radiator s ability to cool the engine or the thermostat could be defective also

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Why is my car losing oil but no leak?

If your car's engine is operating as it should, there will be no need to add oil.Your engine may be burning oil thanks to worn piston rings.Your engine could also be leaking oil thanks to a bad gasket or cracked part.Or you could be losing oil through the head gasket into the cooling system.

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Why won't my blinkers work all lights come on and the flisher signal works but no blinking 95 corsica?

under the steering wheel in you dash is a panel, fuse box under panel, there will be a silver cilider you need to replace. shouldn't be more than 10 bucks

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What is check engine code P0520?

P0520 Code Engine Oil Pressure Sensor/Switch Circuit Malfunction

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Why is my car shaking and engine light on?

Check engine light flashing car shaking is a clear sign of trouble.Vibration or shaking may be caused by misfires, poor fuel pressure, or faulty spark plugs.You should also know that a defective idle air control valve might make the engine idle drop significantly.

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Why is the check light coming on?

There are a number of reasons why a check light might be coming on in your car. Once the check engine light comes on it is important to get the car to a mechanic for diganoses.

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Why is my engine light on and car jerking?

When your car is jerking around, this means that the engine is having a misfire and causing the engine to stumble making the vehicle seem to jerk around.Check the camshaft position sensor for any damage and if the harness is secure to it.Check the spark plugs and wires to see if they have any bur...

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Why is my service engine soon light on?

The intended purpose of the "service engine soon" light is to warn the operator of the vehicle that a malfunction has been detected by sensors in the emissions system of the vehicle.There may be a major problem with the engine or one of its components, but it's usually a minor issue.

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Why is check engine light blinkling on and off on 1996 mercury cougar?

If the check engine light is blinking that means that an engine cylindermisfire has been detected . You can drive it in for repair , just avoid anyrapid acceleration or deceleration because you can damage the catalyticconverter

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What fuse controls the dash panel lights on a 2002 ford focus have checked some but no luck?

see owner's manual - it will specifically tell you what each fuse operates/feeds.is there a rheostat on the headlamp switch (which also may turn fully-on for thedome lamp) that you may have inadvertantly operated in the wrong direction?

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What makes check engine light come on?

For Cheverolet Aveo - the ignition coil is faulty and should be replaced togetherwith new spark plug cable. To start and run smoothly, recommends to change all spark plug to make it more healthy engine.

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Why would a Air bag light came on along with a check engine light?

Crazy as it sounds it could be a voltage problem. You might get an abs light as well. Check the alt voltage for 13.5 or better. If its good you have a real problem and need to get a code reader.

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Why does a 1993 Explorer engine cut out when first pressing on the gas and runs ruff in 1st gear and check engine will turn on but when on freeway check engine light turns off and runs fine?

sounds like a (tps) throttle position sensor. need to have it put on a scanner to check what trouble codes are stored in the ecm.

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What does the warning light on my dash mean What does it mean if the check engine light is on Is my car going to blow up?

It means your car needs attention soon but if the light is flashing it means it needs attention NOW! If you continue to drive the vehicle with the check engine light flashing you can cause serious and expensive damage to the emission system. Either way it's not going to blow up but the repair bil...

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Is car safe to drive with check engine light on?

It really depends on what the cause of the check engine light is.

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Will check engine light come on if transmission is bad?

Transmission problems can cause the check engine light to come on as well, however it's not always as apparent as other components within the vehicle.This can result in a lack of engine power, or the transmission will not respond because there is a problem with it.

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Why does my check brakes light come on in my 1994 Pontiac sunbird and the brakes check out good?

check brake fluid level under hood probaly low

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Can AutoZone tell you why your check engine light is on?

Auto parts store.AutoZone is well known for doing free check engine light diagnostics.Also be aware that AutoZone is in the business of selling parts, not repairing cars, and while many of their staff are knowledgeable, they may not diagnose the problem correctly on the first try.

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Why does the check engine oil level light stay on and the engine keeps cutting off?

Your oil compression is down probably... check the oil pan for rust and such.

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Can you explain why the check suspension light is on in my 2001 ford expedition xlt?

Check your owners manual. If you don't have one copy & paste this link. http://www.genuineservice.com/genuineservice/en/gloveboxresults

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Will remote start work if Check Engine light is on?

If the 'Check Engine Light' or Malfunction Indicator Lamp (MIL) is illuminated, the remote start system will not work.Don't panic, one of the reasons the MIL can illuminate is due to a loose gas cap! Reseal the cap, restart the car, and retry step #1!

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Will vtec still work when check engine light is on?

VTEC may or may not work when the check engine light is on. It depends on why the check engine light is one. If it is on because of a problem with the VTEC system, then, no, it will not work properly.

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Check engine lights on when santro is starts already?

The check engine light (service engine soon) comes on and stays on when a problem is detected by the self diagnosis system of your vehicle. Generally, the problem is in the emissions or something that is affecting the effectiveness of the emissions, but other causes can trigger the light to come ...

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Is it safe to drive with check engine light on?

If the check engine light comes on while you're driving, it can be unnerving.The check engine light means there's a problem somewhere in your emissions system.Regardless, you're safe to drive for now as long as the car isn't performing strangely.Just have the check engine light checked and the pr...

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Will check engine light come on if gas is low?

yes.on some cars, refilling with the engine on (yes, people do that) is enough to set off an EVAP leak DTC which turns the check engine light on, because your fuel cap is off and engine is running.If you don't put your gas cap back on or you don't tighten it correctly or it fails, you can get a c...

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99 3000 gt that died on you while driving There were no warning lights or check engine light the timing belt seems to be ok but you have no spark to your dist of your plugs What could it be?

If you have no spark check with the electrical basics first- battery and alternator.

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Where can I get my engine light checked for free?

AutoZone is well known for doing free check engine light diagnostics.Just go into the store and ask someone behind the counter.

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Why does the check engine light go on and off on a 2003 Harley?

Because there's an intermittent issue which needs to be addressed. You need to have the DTCs (fault codes) read to find out which codes you have, what your active codes are, what your inactive codes are, and how many counts of each fault you have.

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Why does my car smell like gas but no leak?

Even without seeing fuel visibly leaking from your car, if you have a fuel smell, you have a fuel leak somewhere.Usually the cause of a leak is a worn or damaged part, or due to an engine that is not running properly.Also, an engine that is not running properly may produce a fuel smell.

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When check with a decoder and no codes show up?

Your problem is not computer related. Could be a mechanical problem or in need of tune up. Need more info to help you.

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Why does a check engine soon light comes on on a 95 Oldsmobile ciera sl?

That light can mean alot check your break fluid your car is over heating if you still have the manule look in the indexfor the check engine light it will tell you everpage that has to do with that light and what it means

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How do you fix codes P0171 and P0174 in a 99 mercury sable LS with the check engine light on?

Bank 1 and bank 2 is running lean. I would suspect a vacuum leak. Check for cracked, disconnected or broken vacuum line(s). The fuel filter could also be plugged and restricting the flow of fuel.

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Why does my engine light keep coming on?

The mass airflow sensor, or MAF sensor, calculates the amount of air that's coming into the engine so that the computer can add the right amount of fuel.A faulty MAF sensor could trigger the check engine light.It can also cause a car to experience impaired gas mileage, increased emissions or freq...

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My engine light came on after replace valve cover gasket in my 1992 Honda accord but oil is not leaking?

Check your crankcase ventilation, the hose or pcv may be blocked or disconnected.

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How do you clear check engine codes?

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1994 F250 and the check engine light is on what can you check?

usually a problem in the emission control system - have vehicle scanned to determine the problem

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Why does 2003 Ford Taurus run fine but has trouble idling and will sputter and stall and the check engine light is on now?

If the check engine light comes on it is best to take it to a auto part store or mechanic for a diagnosis. They will be able to inform the owner what the issues is.

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What would make my Check engine soon light flash on your Ford 1999 E150?

Hey Ray!I think you should gchnae your blog name to TCMonthly or something like that! Remember the old Women's Day magazine that came out only once a week, then monthly. And the current Women's Weekly that is also just a monthly journal!Or maybe you could do a direct swap of Blog domain name with...

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Will an exhaust leak cause my check engine light to come on?

An exhaust leak can trigger a Check Engine Light due to the fact that depending on the location of the leak, the leak itself is introducing more oxygen into the exhaust gases.When too much oxygen is present due to the exhaust leak, this will cause Check Engine Light to come on.

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Should I drive my car with the check engine light on?

If the check engine light comes on while you're driving, it can be unnerving.Don't panic, though.The check engine light means there's a problem somewhere in your emissions system.Regardless, you're safe to drive for now as long as the car isn't performing strangely.

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How do I reset check engine light on my 02 Mercedes S500.?

Repair the deficiency which is causing it. Even if you reset it, it's just going to come right back if the problem continues to go unresolved.The reason the light is on needs to be fixed first. Once the problem is fixed the light will reset itself once the ECM is satisfied the repair has been don...

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Will a cold air intake make my check engine light come on?

An illuminated Check Engine Light is also a common symptom associated with a problematic cold air intake.If any of the sensors that are installed in the intake detect any issues, they may set off the Check Engine Light to notify the driver of a problem.

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Checking engines codes in 2002 accord?

Many auto parts stores will pull the codes for free and tell you what may be causing the issue. If you want to pull the code yourself they sell code readers for around $100. You need an OBD2 code reader.

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Where can I get my check engine light checked for free?

Auto parts store.AutoZone is well known for doing free check engine light diagnostics.Just go into the store and ask someone behind the counter.

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Why is my engine smoking but not overheating?

The Oil Filler Cap White smoke coming from hood of car not overheating is a common issue in older engines.Older engines produce more hot spots, which make the car smoking under hood but not overheating.Worn out piston rings and clogged PCV tube or valve are the culprits that cause this smoking i...

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Check engine light is on 1995 Mitsubishi eclipse what should you check?

Might Be Yr running out of oil, or water levels are low.

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Why is my engine hot but not overheating?

Thermostat: Another possible issue could be a problem with the thermostat.A vehicle's thermostat is responsible for regulating the amount of coolant flowing through the engine.A broken or malfunctioning one can easily cause your car to overheat.If your vehicle has low oil, it might be causing you...

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Where is the water temp sensor on a Daewoo Lanos 1999 The check engine light has come on and thediagnostic fault code says the car is running at minus 37deg No chance of i being that cold in Australia?

It depends on the engine:- SOHC Cylinder head underneath the ignition coil. DOHC Cylinder Head under underneath the intake nanifold

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What is 2001dodge Dakota check engine code p0031 mean?

Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 1 Sensor 1) symptoms Other than the MIL light illuminating you may not notice any performance issues. cause A short in the O2 sensor heater circuit or the sensor itself A faulty O2 sensor heater Wiring or connectors are broken or frayed to th...

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How serious is a check engine light?

Your Check Engine Light may be indicating a simple problem that's easy to fix—such as a loose gas cap that needs to be replaced.A flashing Check Engine Light indicates that your vehicle's engine is in serious trouble, whereas a steadily lit one means less urgent service is needed.

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How urgent is the check engine light?

A steady check engine light is not as urgent.You still want to get your car in for a diagnostic inspection, but you can work it into your schedule.If a loose gas cap triggered the check engine light, it will reset after several trips.It may take a few days before the light cycles back off.

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Why no light on shifting console?

because the light bulb is bruit out or the is a short in a wire somewhere close or a fuse is out

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Resetting check engine lights?

If you have a Schucks automotive store in your area, go there. They let you use their code reader for free. It reads the code(s). A sales person can then tell you what the codes mean. Afterwards, you can clear the codes using the code reader. If you don't have a Schucks in your area, I'd suggest ...

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